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Guides and Information
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By Geoff Stein (palmbob)
(Editor's Note: This article was originally published on February 28. 2008. Your comments are welcome, but please be aware that authors of previously published articles may not be able to promptly respond to new questions or comments.) Cold hardiness is not a very easy adjective to define. I do not know if this is true with all plant groups, but it most certainly is the case with palms. And of course it is a relative term. Since most palms are from the tropics, any palm that can survive outside a tropical environment is considered cold hardy. But a cold hardy palm is a wimp compared to many plants that live where it freezes every winter. The cold-hardiest palm can survive in zone 6 and not really any lower than that outdoors. For a discussion on the factors that influence cold hardiness in palms and more about what cold hardiness means, please see the related article coming out soon after this one. Below is basically a list of SOME of the cold hardy palms of significance, both well known and newly realized. It is not by any means an exhaustive list of all the cold hardy palms or even a large fraction them. It would simply be impossible to cover them all in a 'small' article here in Davesgarden. This is only meant as an introduction to get the reader aquainted with what palms they might be able to grow, and some place to start. For further information, see recommendations at the bottom of the article and the plantfiles on this site. Acoelorrhaphe wrightii (Silver Saw Palm or Everglades Palm): This is a native of Florida and the Caribbean. Acoelorrhaphe is a suckering fan palm with hardiness to about 22F-24F (-5.5C to -4C). It is not a very commonly grown palm in private gardens since it can end up taking up a lot of room. But if keep pruned of lower leaves and excessive canes, it can be a highly ornamental and easy palm. It is very slow-growing though, and it may take over ten years in cooler climates to get large enough for one to appreciate this as a palm.
Acrocomia aculeata/totai is a moderately hardy species that looks like a Queen Palm, only very spiny, can handle cold to about 26F (-3C)
Allagoptera arenaria (Seaside palm): Probably one of the most "user-friendly" (i.e., no spines or sharp leaves) palms, this is another relatively rare species in cultivation, again primarily due to its very slow growth. Five-year-old palms often still have their strap leaves. It is a slowly offsetting trunkless pinnate species with curly leaflets. Allagoptera arenaria has pretty good cold hardiness to about 25F, and it is a good palm in both sun and shade. It also has remarkable salt tolerance and can be grown along the shoreline. Other Allagopteras may be similarly hardy, but they are much rarer and some even impossible to find.
Archntophoenix cunninghammiana (King Palms) and Archontophoenix purpurea, California Not one of the most cold hardy genera, Archontophoenix (aka the King Palms) do well in Southern California rarely dying from periodic freezes, but do show damage between 25F and 28F (-3.8 to -2C) Arenga engleri (Dwarf Sugar Palm): With hardiness about 22F-23F (-5.5C to -5C), this is a relatively popular species thanks to widespread availability and a moderate growth rate. This pinnate, suckering species is not only cold hardy but can tolerate deep shade as well as full, hot desert sun, and cares little about winds. It also has another perk in having incredibly good smelling flowers. Though it can get fairly large and wide, it is easy to prune offshoots off and keep it neat and ornamental.
Beccariophoenix madagascariensis and 'no windows' in California Beccariophoenix is a mildly cold hardy genus of at least 2, possibly three species, from Madagascar, tolerating temps down to about 27F (2.7C) This palm was already discussed in the article on Blue Palms, but it is one often forgotten by those who make lists of cold hardy palms. The mature blue form of this species can survive temps in the low 20s (-6.6C to -5C) thought leaf damage is extremely variable depending on climate and type of freeze (sometimes severe leaf damage will occur at temps in the high 20s). It is a magnificent palm and should be tried by anyone with enough room in a marginal climate. This palm grows well ONLY in full sun, but does great on both US coasts (though tends to look far more impressive on the east coast). It is a relatively fast grower and has a high tolerance to wind and heat.
Though NOT a good palm for Southern California, this palm is considered cold hardy in Florida where it grows well in zone 9b getting minimal damage at temps down to about 24F (-4.4C)
Braheas: Since all the Braheas are cold hardy, they will be discussed as a group here. These are Central American fan palms that prefer arid, low-rainfall climates over the more humid, muggy climates favored by the majority of palms. The most commonly grown species of this genus are Brahea edulis (Guadalupe Palm) and Brahea armata (Mexican Fan Palm). Both are fairly common landscape palms, and Brahea edulis can be seen grown all over southern California as a street tree. Eventually the same may be said about Brahea armata as its use is increasing yearly. Most Braheas are hardy from 20F-25F (-6.6C to -3.8C), but Brahea armata is remarkably tolerant of freezes handling cold snaps down to nearly 10F (-12C). All the Braheas are highly ornamental and excellent garden palms, but some are very rare and/or incredibly slow and will never catch on as public landscaping palms.
Brahea armatas Brahea decumbens Brahea aculeata
Brahea nitida Brahea pimo Brahea eudulis pair
Butia capitata (Jelly Palm): Butia is another South American palm genus that has a number of cold tolerant members. Perhaps all are cold tolerant, but many species are so rare they have not been tested yet. Butia capitata is the most common species in this genus and it is easily the most cold hardy and versatile feather palm in cultivation, tolerating lows as cold as 15F (-9.5C) or lower, and growing equally well on the east U.S. coast as it does on the west coast. It does tolerate some shade, but is ideally a sun plant. This is also a moderately fast grower so it, too, has become a popular landscaping palm throughout the world including the marginal climate zones. This is one of the easiest palms to grow. And it has the additional perk of having tasty, edible fruits.
Butia capiata Butia capitata Butia paraguayensis
Butia x Syagrus Butia X Syagrus Butia x Jubaeas Butia hybrids are also very useful and cold hardy landscape palms, usually showing cold hardiness to about the same as Butia capitata Caryota urens (Toddy Palm or Fishtail Wine Palm): Though several other Caryotas have pretty good cold tolerance, this is the most commonly grown Caryota species with notable cold hardiness (about 25F or -3.8C). Caryota ochlandra may be more cold hardy, but it is a rarer palm, and looks a lot like Caryota urens. Caryota gigas is rapidly overtaking Caryota urens in popularity thanks to its massive size and highly ornamental leaves, but it is less cold tolerant with significant damage at around 27F (-2.7C). Caryotas are called the Fishtail palms because the leaflet shape is similar to that of a fish’s tail. These are the only bipinnate palms (their fronds branch again). And they are monocarpic (die after flowering). Though one of the fastest growing palms in cultivation, Caryota urens have not become too popular thanks to their short lived nature (many only live 15-25 years), toxic fruits and unnerving tendency to blow over with little warning.
Caryota urens Caryota gigas
Ceroxylons have some cold hardiness, growing naturally at very high elevations in northern South America, handling temperatures 3 or 4 degrees below freezing Chamaedorea microspadix and C. radicalis: These two Chamaedoreas are unusual members of their genus as most of the rest are only very marginally cold hardy. The Chamaedoreas are Central American palms and are pinnate single to suckering, mostly understory species. The two species listed here are not only unusually cold hardy (both down to around 20F) but tolerate far more sun than do most other Chamaedoreas. Chamaedorea microspadix is a suckering, slow-growing palm with skinny stems and bright red seeds. Chamaedorea radicalis is a solitary species that either forms a tall trunk, or none at all, and has long, leathery deep green leaves. These two species grow a bit better in California than in the hot, humid climates of the eastern U.S. coast. They both perform well as potted plants, too, but need a lot of light to do well indoors.
Chamaedorea microspadix in full sun Chamaedorea radicalis group with a few tree forms mixed in Chamaedorea radicalis tree form
Chamaedorea costaricana, Chamaedorea elegans and Chamaedorea ernestii-augustii also have some cold tolerance
Chamaedorea oreophila, Chamaedorea adcendens and Chamaedorea plumosa have slightly more cold hardiness than the average Chamaedorea
Chamaerops humilis (Mediterranean Fan Palm): Probably one of the most commonly grown specimen landscape palms throughout the subtropical and warm temperate world, Chamaerops have cold hardiness to nearly 15F (-9.4C). This suckering fan palm grows moderately fast but, still, large specimens are worth a lot of money. Though native to a European temperate climate it is also an excellent plant for desert climates, having very high heat, sun, wind and drought tolerance. And it can be grown in the shade, even indoors, but is happier in full sun. The blue form of this (variety cerifera) is probably as hardy, but it has not been fully tested yet.
Two large Chamaerops humilis and a potted Chamaerops humilis var. cerifera in southern California
Chuniophoenix is a surprisingly hardy genus, tolerating temps into the mid 20s (-4.4C to -3.3C) with little or no damage
Copernicia alba (Caranday Palm): This South American palm is the hardiest of the genus, of which most others are anything but cold hardy. Copernicia alba is a slow growing, solitary fan palm- a dangerously sharp species (very sharp spines on the petioles) that tolerates lows to about 25F (-3.8C), perhaps lower. The closely related Copernicia prunifera (Carnuba Wax Palm) may have similar tolerance but seems to even more slow growing (a characteristic consistent throughout the genus). Copernicia glabrescens and baileyana also have some cold hardiness though are grown far less commonly. The latter palm, Copernicia baileyana, is a massive and highly ornamental fan palm with a huge, concrete-like trunk and nearly perfectly symmetrical, stiff circular leaves. Sadly it is an agonizingly slow growing palm and most planters of this species won’t live long enough to see it grow into a mature palm.
Copernicia baileyana seedling in California and adults in Thailand Copernicia prunifera in Thailand
Cyphophoenix elegans is one of the most cold tolerant of the New Caledonian palms, handling temps to about 26F (-3.3C) without damage
Dypsis decpiens (Manambe Palm): Though this is another incredibly slow growing species, it is worth waiting for. And if planted large enough, and if the planter is young enough, it might be worth planting- a mature specimen is one of the most amazing and ornamental palms one can grow. This Madagascan species is probably one of the two hardiest species from this island (Bismarckia being the other) and is a suckering, massive pinnate palm with a swollen and ornamentally ringed trunk. This is a very rare species commercially for the obvious reason of it’s being so slow. But it also is a difficult palm when young, so it is recommended to obtain the largest specimen possible for multiple reasons. It is hardy to about 24F (-4.4C) and is one of the few palms that grow much better on the west coast than on the east coast (not sure why- may be a soil problem).
Dypsis decipiens adult and maturing juvenile Dypsis saint lucei is one of the few other cold hardy Dypsis sp. tolerating temps into the mid 20s
Guihaia argyrata is a low and slow growing suckering fan palm hardy to about 20F (-6.6C)
Hedyscepe is a monotypic genus from Lord Howe Island (where Kentia palms come from) that has mild cold hardiness to about 28F (-2.2C) Howea forsteriana (Kentia Palm): Most anyone who grows palms, or has visited a mall, is familiar with this species as it is one of the most commonly grown palms in cultivation. The reason for that is it is the premiere house palm. But it is also a good landscape palm having hardiness to about 26F (-1.6C) (gets some burn at temps under 29F if significant frost, though). Considered a moderately growing species, this solitary feather palm prefers situations with mostly morning sun, or coastal sun, and not too much wind. It is not a great palm for inland desert sun. It has a wonderfully ringed, green trunk with ornamentally drooping leaflets unlike most other palms, and that creates a unique tropical effect. The related Howea belmoreana is less hardy still and only barely fits the definition of a cold hardy palm.
Howea forsteriana in garden, and colony in park, California Howeas of both species (belmoreana on left and forsteriana on right)
Jubaea chilensis (Chilean Wine Palm): Considered the largest palm in the world, at least in terms of girth, this giant from Chile has a remarkable degree of cold hardiness, surviving freezes down to about 15F (-9.5C). It is a solitary, pinnate palm with a smooth trunk. Though not a fast grower, it tends to pick up speed once a trunk is formed… but it can take up to 15 years for it to get to that point. This is another one of those exceptional palms that grows far better on the US west coast than the east coast (in fact, it seems nearly impossible to grow there). It is also a highly drought and wind tolerant plant, but seems to resent intense year round heat.
Jubaeas in California showing several variations in crown shape younger palm in private garden
Jubaeopsis is a monotypic South African genus cold tolerant down to about 24F (-4.5C)
Most Licualas are fairly tropical in their needs, but Licuala spinosa stands out as being the cold hardiest in the group on both the east and west coast, tolerating temps into the mid 20s (-4.4C to -3.3C) with minimal damage Livistonas: This is another genus that has a number of cold hardy palms in it, though not all Livistonas are very cold hardy. Probably the most well known species is Livistona chinensis, the Chinese Fan Palm, a very commonly grown palm on both US coasts and hardy to about 20F (-6.6C) or close. Livistona australis, decorum, nitida, mariae and saribus are probably nearly as cold hardy and all except saribus are much faster growers. These are all solitary droopy-leaved fan palms with very sharp petiolar teeth. Most cold hardy Livistonas are from Australia, but L chinensis is from China and Japan, and Livistona saribus is also from China, and nearby Asian islands. And not every Livistona from Australia is cold hardy (the ‘miniature species are not). Most cold hardy Livistonas grow well on both coasts. And Livistona chinensis performs tolerably as a house plant.
Livistona australis young plants adult Livistona australis pair pair of adult Livistona decorums (aka decipiens)
Livistona chinensis young Livistona mariae maturing Livistona saribus
Nannorrhops ritchiana (Mazari Palm): This is about the only plant that can survive the brutal extremes of the mideastern environment and it has a very large climate range in which it performs well. It is cold tolerant down to about 10-15F (-12C to -9.5C), but it is also very drought tolerant, sun and heat tolerant as well as tolerant of humid, tropical climates. Still, it can be a tricky palm when young and is pretty slow growing. It is a suckering fan palm with blue-green to pale green leaves and relatively harmless petioles. It is a rare palm in cultivation primarily due to its slow growth and finicky nature as a seedling.
adult Nannorrhops green form young Nannorrhops blue form
Oraniopsis is a monotypic Australian species with cold hardiness similar to Ceroxylons (related genus)
Parajubaeas: These South American solitary pinnate palms are one of the ‘newer’ landscape palms for the U.S. west coast (don’t tolerate warm, humid climates well) and have some cold tolerance to about 25F (-3.8C). These are still pretty rare in cultivation mostly due to their irregular and unpredictable germination. But once this barrier is overcome, they tend to be pretty fast and easy palms only suffering from excessive cold and overhead watering (easily get but rot from this practice). Though Parajubaea cocoides is the most commonly grown species, it is the slowest and least tolerant of high winds and blasting inland heat. The other two species, torralyi and sunkha are much faster growers and have more tolerance of climate variations.
Parajubaea cocoides grouping Parajubaea sunkha
Phoenix species: All of the Phoenix species are considered cold hardy, though some are much more cold-hardy than others. Most growers and landscapers are very familiar with this genus as they are relatively fast growing and versatile palms, tolerating a wide range of climates and soils. Most are some of the easiest palms there are to grow, and many are quite available. The most commonly grown include Phoenix canariensis, a massive, solitary species from the Canary Islands and probably the fastest growing of the genus, and also one of the fastest of all palms in cultivation. It is cold hardy to around 22F-24F though it seems hardier on the west coast than the east coast. Phoenix dactylifera, the true date palm, from Northern Africa, is cold hardy to about 20F (-6.6C) and also a fast grower. This is probably the second most commonly grown palm on earth and one of best Phoenix palms for desert climates. Phoenix reclinata, the Senegal Date Palm, a suckering moderately fast growing palm from Africa, is hardy to about 22F-24F (-5.5C to - 4.4C), but this information is based on the palms currently in cultivation, most which are hybrids of this species, not the ‘pure’ thing (hybrid Phoenix are extremely common). And Phoenix roebellenii, probably the most commonly grown landscape Phoenix palm in the US, is cold hardy to about 26F (-3.3C), which isn’t too shabby considering it originates from tropical Asia.
Phoenix canariensis miles of Phoenix canariensis along Pacific coast Phoenix dactyliferas in California
Phoenix loureieri Phoenix reclinata Phoenix rupicola
Phoenix sylvestris Phoenix theophrastii Phoenix roebelleniis
Plectocomia is a rattan genus with several tropical species, but Plectocomia himalayana is remarkably cold tolerant to at least 25F (-3.8C) and possibly lower
Ravenea rivularis in Hawaii and in California Ravenea xerophila in California Ravenea is a genus of Madagascan palms, some which qualify as cold tolerant, but barely. The most well known is the Majesty Palm, Ravenea rivularis, cold tolerant to about 28F (-2.2C). Ravenea xerophila is a surprisingly cold tolerant slow heat-loving plant handling temps to about 25F (-3.8C) with only slight leaf damage Rhapidophyllum hystrix (Needle Palm): This native U.S. palm tolerates cold better than any other palm and can grow in climates as ‘inhospitable’ as Washington, DC. It tolerates temps down to around -10F (-23C), though probably not for an extended period of time. It is a suckering, slow-growing fan palm with a wide range of climate tolerances. Though not ideal as a desert palm, it does grow well in southern California where it gets pretty hot, and I have seen it growing happily in tropical Thailand. Still, it is too slow to be a popular landscape plant, and some find its scrubbiness less than ornamental.
Rhapidophyllum hystrix Rhapidophyllum next to a Chamaerops in botanical garden
Rhapis excelsa (Lady Palm): Commonly seen as an indoor palm, this species also performs well as an outdoor landscape understory species, tolerating temps down into the low 20s ( around -5C to -4C). It is a slow growing palm, but this one looks ornamental even at a small size. It is possible native to China, but is actually unknown in the wild. This suckering palmate species is one of the easiest palms to grow, tolerating mild drought, lots of water, very dark, shady gardens and is very resistant to most diseases. There are several other Rhapis species, all considered at least somewhat cold hardy, and Rhapis humilis and multifida are probably nearly as hardy.
Rhapis excelsa Rhapis humilis Rhapis multifida
Rhopalostylis is a genus from New Zealand and some surrounding islands that has mild cold hardiness to the upper 20s (around -2.2C)
Roystoneas have mild cold tolerance that improves with age, with adults of some species tolerating temps into the high 20s (around -2C) Sabals: These palms are some of the hardiest and adaptable known in cultivation. All are considered cold hardy, though the range is broad with some only tolerating temps into the high 20s (around -2.4C) (Sabal mauritiiformis and Sabal yapa) while others tolerate temps down below 10F (-12C) (Sabal minor). Most of the rest do OK with temps down into the teens. These are all solitary costapalmate species from North to South America. Most are slow growing, though they grow much faster on the east coast than on the west coast. They are also relatively drought, heat and wind tolerant (except the two least cold hardy above). To me, most Sabal species tend to look alike, with only subtle differences notable. Some Sabals are common in cultivation, though most are only commercially available in the eastern U.S.
Sabal bermudana Sabal domingensis immature Sabal domingensis
Sabal etonia on left and Sabal minors on right Sabal mauritiiformis in California Sabal palmettos in Florida
Serenoa repens (Saw Palmetto): Native to the southeastern U.S., this palm has remarkable hardiness to a wide variety of climate extremes, from heat, to cold (15F or -9.5C), windy, hot and sunny, shady, sandy to muddy soils etc. This is a suckering fan palm that is very slow growing on the west coast and only somewhat slow on the east. It is not used much as a landscaping palm in the east since it is so common, most consider it a weed. While on the west coast it is also rare since it is so slow growing it is impractical as even a garden plant save for those with a lot of patience. Some forms are quite silver and highly sought after, at least relative to the ordinary green-leaved plants.
Syagrus romanzoffiana (Queen Palm): Probably the second most commonly used landscape palm in the U.S. thanks to its cold hardiness (23F-24F or -5C to -4.5C), ease of planting/moving and growth rate (very very fast). It is a solitary feather palm that has the potential of being an excellent specimen palm, but is usually under-watered and over pruned in public landscapes giving it a sickly, weak appearance and an undeserved reputation as an ugly palm. A few other Syagrus species have good cold hardiness, too, but not as much as this species.
Syagrus romanzoffianas Syagrus coronata in California Trachycarpus species (Windmill palms): All the Trachycarpus are cold hardy, though some are much more cold hardy than others. Trachycarpus fortunei and wagnerianus are probably the most cold hardy, able to grow in regions where it gets down to 10F (-12C). Most others are only hardy into the mid 20s (around -3.8C). Trachycarpus fortunei is one of the most commonly planted landscape palms along the entire US west coast, and like the Queen palms, usually looks terrible due to under watering. All these are solitary fan palms from Asia and most are moderate growers, though some are considered fairly slow.
Trachycarpus fortuneis Trachycarpus fortuneis Trachycarpus wagnerianus group
Trachycarpus martianus Trachycarpus oreophila and princeps Trachycarpus takil (maybe)
There are three species of Trithrinax, all fairly cold hardy, but only one is ‘common’. Trithrinax brasiliensis is a solitary (rarely suckering) fan palm with remarkably long, thick spines, closely and sloppily arranged along its trunk. It is cold hardy down to about 15F (-9.5C) as is Trithrinax campestris, the second most common species. Trithrinax campestris is a suckering, slower palm with blue-green leaves and an extremely well-armed palm- not only is its trunk armed somewhat like that of Trithrinax brasiliensis, but each leaf is very stiff and ends in a needle-like point making this one of the worst palms to prune or plant near a walkway. However, both palms are fairly ornamental.
Trithrinax brasiliensis crown and fruit young Trithrinax brasiliensis Trachycarpus campestris
Washingtonia filifera and W. robusta (California and Mexican Fan Palms): Some consider these the same species, but they certainly seem to have different cultivational limits, as well as come from two relatively distinct populations- one in Southern California and the other in Mexico. The latter is the most commonly planted landscape palm in the US, thanks to its ultra-fast rate of growth, ease of cultivation (highly adaptable to most soils, heat, wind and drought) and cold hardiness (hardy to about the mid to low 20s or -5.5C to -4C). The California palm seems to have a good deal more cold hardiness showing little damage down to below 10F (-12C), but is climatically less versatile as it performs poorly near the coast and in humid climates. It is also a slower grower, but still fast relative to most palms.
Washingtonia robustas with skirts Washingtonia filiferis both Washingtonias in California There are dozens and dozens more palms that qualify as cold hardy, but these are the most common and important economically at this time. But if one gets bored collecting and growing these, just peruse the plant files for more ideas. For more on Cold Hardy Palms, see Betrock’s Cold Hardy Palms by Alan Meerow, or Palms for Southern California by Geoff Stein (me), both available through the International Palm Society Bookstore. For a good website on cold hardiness in palms, check out Palmpedia.com Thanks to growin for use of the thumbnail photo of the Trachycarpus in the snow
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Acoelorrhaphes in California
Allogoptera arenaria in California
Arenga engleri in California
Bismarckias in Thailand and CA
Borassus aethiopium in Florida
Ceroxylon quindiuense in southern California
Chuniophoenix nana in California
Copernicia alba in California
Guihaia argyrata in California
Hedyscepe canterburyana in California
Jubaeaopsis caffras
Licuala spinosa
Oraniopsis appendiculata in California
Plectocomia himalayana in California
Rhopalostylis species in California
Roystoneas regia and borenquinia
Serenoa repens
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